Much attention had been directed in recent years toward genes for NAD+-dependent deacetylases known as sirtuins, as longevity genes. The Sir2 gene was first identified in yeast, and in experimental systems using lower animals such as yeast and nematodes, it has been reported that lifespan is shortened by deletion of Sir2, while lifespan is lengthened when it is overexpressed (NPLs 1 and 2). The Sir2 gene is conserved in mammals, with sirtuin-1 to sirtuin-7 having been identified. Much attention among these has been focused on sirtuin-1, as it is the one with a structure and function most resembling yeast Sir2.
The protein target of sirtuin-1 has been identified, and research suggests that it is involved in intracellular metabolism, energy consumption, and inflammation and stress response pathways. In addition, activation of the sirtuin-1 gene is thought to have effects for arteriosclerosis, diabetes, heart disease, cancer, diabetes complications, neuropathic pain, microvascular dysfunction, life extension, mitochondrial disease, mitochondrial myopathy, neurodegenerative diseases (such as Alzheimer's disease, amyotrophic lateral sclerosis and Parkinson's disease), chronic obstructive pulmonary disease (COPD) and psoriasis (NPLs 3 and 4).
Among sirtuin activating substances there are known polyphenol compounds, which include resveratrol found in grape peels and the like or fisetin found in strawberries and apples, and non-polyphenol compounds such as SRT1720. The major pharmaceutical company GlaxoSmithKline plc of England is vigorously conducting development of sirtuin-1 activating substances, and for example, SRT2104 which has been reported to be effective for prevention of type 2 diabetes, osteoporosis, sarcopenia and skeletal muscle atrophy (Reference 5) is currently in the clinical trial stage.
In addition, it is known that Peucedanum japonicum Thunb. plant body and its extract has action of inhibiting disaccharidase and efficacy for prevention and treatment of diabetes as well as countering obesity (PTL 1), has a cell-activating effect, antioxidant effect and melanin production inhibiting effect (PTL 2), exhibits inhibitory action against heparanase activity and is effective for preventing and improving wrinkles (PTL 3), and promotes ceramide synthesis (PTL 4).
Peucedanum japonicum Thunb., also known as “longevity grass”, is a plant of which it has been traditionally said in Okinawa Prefecture, that “eating one serving extends the life by a day”. Sirtuin genes have already been known as longevity genes for over 15 years. However, absolutely no previous reports exist regarding whether the plant body or extract of Peucedanum japonicum Thunb. has a sirtuin-1 activating effect, and finding the connection between these has not been an easy task. Since traditional accounts regarding Peucedanum japonicum Thunb. and longevity do not constitute scientific evidence, it has not been easy to establish a connection between them.